Cosmetic and personal care products for use on keratinous substrates such as skin and hair are available commercially in various forms, for example, as creams, lotions, gels, pastes, and powders. Regardless of the form, these products have to achieve and provide certain benefits and attributes such as efficaciousness, cosmeticity, desirable texture, stable formulations, and ease and convenience of use and application. Moreover, changing market needs present an opportunity to produce cosmetic and personal care products that are readily available and easy and convenient for the consumer to use, store, and travel with, as well as provide cost savings to the manufacturer in terms of processing, storage space and transport.
Thus, products that are commercially available in powder form have the advantage of ease of transportability, packaging, and storage. However, products in powder form may require a wetting or mixing step with water in order to form ready to use compositions immediately prior to use. Thus, aside from the formulation challenge of providing a stable powder composition that is easy to mix or disperse in an aqueous composition, the powder composition must be formulated in such a way that the resulting ready to use compositions have a texture and viscosity such that it is easy to apply onto surface and does not drip or run. If the powder composition contains active agents or ingredients that are designed to provide a particular effect on the treated surface, it is also desirable that the efficacy of such ingredients be preserved in the powder composition and in the ready to use compositions.
One such product that may be available in powder form but which is generally contacted with water or an aqueous composition prior to use is a depilatory composition. Depilatory compositions are employed for removing superfluous body hair and include a compound, such as a compound containing a thiol group, that degrades hair keratin or that aids in removing hair.
According to the present invention there is provided a depilatory composition in the form of a powder comprising an alkaline material comprising a hydroxide-containing compound, at least two carbonate compounds, a sulfur-containing compound, a silica material, a liquid fatty substance, an acrylic polymer, wax, and a chelant compound. The powder composition of the invention is capable of being contacted or mixed with an aqueous composition in order to form a ready to use composition having a depilatory effect when applied onto a keratinous substrate such as skin with hair or hair. The ready to use composition is formed either in situ on the keratinous substrate or in a vessel prior to application onto the substrate.